feat(corelib): OptionTrait::map_or, OptionTrait::map_or_else

[julio4]

OptionTrait::map_or

Returns the provided default result (if none), or applies a function to the contained value (if any).

Example

assert_eq!(Option::Some("foo").map_or(42, |v| v.len()), 3);

let x: Option<ByteArray> = Option::None;
assert_eq!(x.map_or(42, |v| v.len()), 42);

OptionTrait::map_or_else

Computes a default function result (if none), or applies a different function to the contained value (if any).

Example

let k = 21;

let x = Option::Some("foo");
assert_eq!(x.map_or_else( || 2 * k, |v: ByteArray| v.len()), 3);

let x: Option<ByteArray> = Option::None;
assert_eq!(x.map_or_else( || 2 * k, |v: ByteArray| v.len()), 42);

[reviewable-StarkWare]

This change is 

[enitrat]

Reviewable status: 0 of 2 files reviewed, 2 unresolved discussions (waiting on @julio4)

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corelib/src/option.cairo line 356 at r2 (raw file):

    /// or applies a function to the contained value (if any).
    ///
    /// Arguments passed to `map_or` are eagerly evaluated; if you are passing

I don't believe this applies

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corelib/src/option.cairo line 368 at r2 (raw file):

    ///
    /// let x: Option<ByteArray> = Option::None;
    /// assert_eq!(x.map_or(42, |v| v.len()), 42);

This does not compile

Code quote:

    /// assert_eq!(Option::Some("foo").map_or(42, |v| v.len()), 3);
    ///
    /// let x: Option<ByteArray> = Option::None;
    /// assert_eq!(x.map_or(42, |v| v.len()), 42);

[julio4]

Reviewable status: 0 of 2 files reviewed, 2 unresolved discussions (waiting on @enitrat)

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corelib/src/option.cairo line 356 at r2 (raw file):

Previously, enitrat (Mathieu) wrote…

I don't believe this applies

Is it different than rust?

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corelib/src/option.cairo line 368 at r2 (raw file):

Previously, enitrat (Mathieu) wrote…

This does not compile

Done.